b

The definition of b is the second letter of the English alphabet.

(noun)

An example of b is the first letter of the word "bottle."

See b in Webster's New World College Dictionary

or B

noun pl. B's, b's

the second letter of the English alphabet: from the Greek beta, a borrowing from the Phoenician
any of the speech sounds that this letter represents, as, in English, the (b) of boat
a type or impression for b or B
the second in a sequence or group
an object shaped like

adjective

noun

a blood type
☆ Educ. a grade indicating above-average but not outstanding work: a B in French
Music
1. the seventh note or tone in the ascending scale of C major
2. the scale having this tone as the keynote
3. a note representing this tone
4. a key, string, etc. producing this tone

adjective

☆ second-class; inferior to the best: a B film

Also, for 1-2, 4-6, 8, 10, 12-13, 16-17, & 19, b

bomber: used in designations for aircraft: B-52

See b in American Heritage Dictionary 4

noun pl. B's b's or B's also bs or Bs

The second letter of the modern English alphabet.
Any of the speech sounds represented by the letter b.
The second in a series.
Something shaped like the letter B.
B The second best or second highest in quality or rank: a mark of B on an English theme.
Music
a. The seventh tone in the scale of C major or the second tone in the relative minor scale.
b. A key or scale in which B is the tonic.
c. A written or printed note representing this tone.
d. A string, key, or pipe tuned to the pitch of this tone.
B One of the four major blood groups in the ABO system. Individuals with this blood group have the B antigen on the surface of their red blood cells, and the anti-A antibody in their blood serum.